wg-quick: syntax error, unexpected saddr

[Eddie]

First time running wireguard as a native client on my Slackware 14.2 
system throws this:

root at The-Tardis:~# wg-quick up wg0
[#] ip link add wg0 type wireguard
[#] wg setconf wg0 /dev/fd/63
[#] ip -4 address add 192.168.150.14/32 dev wg0
[#] ip link set mtu 1420 up dev wg0
[#] wg set wg0 fwmark 51820
[#] ip -4 route add 0.0.0.0/0 dev wg0 table 51820
[#] ip -4 rule add not fwmark 51820 table 51820
[#] ip -4 rule add table main suppress_prefixlength 0
[#] sysctl -q net.ipv4.conf.all.src_valid_mark=1
[#] nft -f /dev/fd/63
/dev/fd/63:5:76-80: Error: syntax error, unexpected saddr

Fairly simple config to connect to my VPS:

[Interface]
Address = 192.168.150.14/32
PrivateKey = <Not the key you're looking for>

[Peer]
PublicKey = <Just being overly paranoid>
Endpoint = www.xxx.yyy.zzz:51820
AllowedIPs = 0.0.0.0/0

Not sure what additional information you need collected at this point.

I'm able to connect outbound successfully using NordVPN's version of 
wireguard, but that doesn't use wg-quick, which is where the issue is.

Cheers.